Are function pointers never dangling?

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Assessment

Difficulty
1/5
Estimated time
1-3 hours
Newbie friendliness
62/100
Issue type
Documentation
Clarity
Clearly specified
Activity status
Stale
Tech stack
rust
Domain
documentation

Research direction

Start with the linked Reference sections on undefined dangling pointers and pointer type kinds, and compare how function pointers fit their definitions. Clarify the dangling-pointer wording so its treatment of function pointers is unambiguous; the linked sections should reflect the resolved explanation.

Written by the indexing model from the issue text.

Description

https://doc.rust-lang.org/stable/reference/behavior-considered-undefined.html#r-undefined.dangling says:

A reference/pointer is “dangling” if not all of the bytes it points to are part of the same live allocation (so in particular they all have to be part of some allocation).

According to https://doc.rust-lang.org/reference/types.html#r-type.kinds

Pointer types:

  • References
  • Raw pointers
  • Function pointers

The function pointers are categorized into pointer types. However, a function pointer is never dangling in a program. This should be clarified in section r-undefined.dangling.

Dominant language
Rust
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